1. Field of the Invention
The present invention relates to a liquid discharge device having a head for discharging liquid from a nozzle.
2. Description of the Related Art
Liquid discharge devices having a head for discharging liquid such as ink or the like from a nozzle are widely known. For example, ink jet printers are an example of a liquid discharge device. For example, some ink jet printers include a cap that covers a nozzle plane of the head, and a negative pressure source connected to the cap. The negative pressure source is driven while the cap is covering the nozzle plane. Old ink present in the nozzle is thus sucked out.
When the ink in the nozzle is sucked out, this ink adheres to the cap. The following technique has been proposed to remove the ink adhering to the cap. That is, the following is taught in Japanese Patent Application Publication No. 6-126947: after the ink of the nozzle has been sucked out, the negative pressure source is driven while a space is formed between the cap and the nozzle plane of the head. Below, supplying negative pressure to the cap after the ink of the nozzle has been sucked out is termed vacuum sucking.
In the aforementioned technique, the vacuum sucking is performed while the cap is facing the nozzle. The space between the nozzle plane and the cap is small. In this case, there is the possibility that ink is sucked from the nozzle when the vacuum sucking is performed. When ink is sucked from the nozzle, this ink adheres to the cap. In this technique, there is the possibility that the vacuum sucking causes the ink to adhere to the cap.
If the space between the nozzle plane and the cap is increased, the ink would probably not be sucked from the nozzle. In this case, however, a large negative pressure cannot be applied to the ink adhering to the cap, and the ink cannot be efficiently removed from the cap.